Microtome



No. 618,5!4. Patented Jan. 31, I399.

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MIGROTOME.

(Application file d Sept. 10, 1897.)

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No. 6|8,5l4. Patented Ian. 3|, I899 W. LUW.

MIGROTOME.

(Application filed Sept. 10. 1897.

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(No Model.)

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NITED STATES FFrcE.

PATENT \VILHELM LOW, OF HEIDELBERG, GERMANY, ASSIGNOR TO THE FIRM OF R.JUNG, OF SAME PLACE.

MIGROTOME.

SPECIFICATION forming part of Letters Patent No. 618,514, dated January31,1899.

Application filed September 10, 1897. Serial No. 651,216. (No model.)

To aZZ whom, it may concern.-

Be it known that I, WILHELM Low, a subject of the Grand Duke of Baden,residing at Heidelberg, in the Grand Duchy of Baden, German Empire, haveinvented new and useful Improvements in Microtomes, of which thefollowing is a specification.

My invention relates to improvements in microtomes or machines forproducing thin sheets or blades from objects that are to be examinedmicroscopically.

The improvements consist in means for producing said sheets or bladesfrom objects of any kind with such accuracy in obtaining the thicknessesrequired of the sheets as hitherto never has been possible to obtain,said means relating to a new manner of guiding the knife or cutter andthe knife-carrier itself, a new manner of combining the object-carrierwith the adjusting device, and a new mode of supporting and adjustingthe object-carrier and of fixing it in any desired position. I attainthese objects by mechanisms as illustrated in the accompanying drawings,in which- Figure 1 is a front view of the entire ma chine. Fig. 2 is atop view thereof; Fig. 3, a side view of the machine, taken from theright side of it. Figs. 4: to 11 represent parts of the machine on agreater scale-name1y, Figs. 4 and 5, the knife-carrier in front and sideviews; Fig. 6, the object-carrier; Fig. 7, a sectional view thereof,taken on line 7 7 in Fig. 6; Fig. 8, a cross-section of said carrierfollowing the line 8 Sin Fig. 6. Fig. 9 is a top View of the micrometermechanism; Fig. 10, a side view; and Fig. 11, partly taken in section, adetailed side view thereof.

Similar letters refer to similar parts throughout the several figures.

The foundation-plate B and the standards A A, having fixed to them theprisms 0' C constitute the framework of the machine. The adj oiningsurfaces of the two prisms form an acute angle, as shown in Fig. 3, andon the surfaces, which are made exactly plain, the knife-block D iscaused to slide. To reduce the friction as much as possible, slidepiecesa may be provided on the surfaces of block D. On the knife-block D isfixed the knife-carrier E by means of thumb-screws?) b, curved slots 1)in the knife-carrier allowing the latter to be adjusted, if required.The projecting ends of the knife-carrier are formed as bearings for theknife F, one end of which terminates in a ball 0 and the opposite end ina pivot c of partly-cylindrical surface, means, such as set-screws d (I,being provided to fix the said pivots of the knife in its bearings. Asclearly shown in Figs. 4 and 5, the cylin-. drical surface of the pivotc is partly cut away, so as to secure exactly the required inclinationof the cutting edge of the knife F towardthe object. This arrangementallows the knife to be secured with great accuracy without bending it.

On the pillar G, projecting upward from the bed-plate B, there arejournaled upon the pivot-points e e two levers H H forming, with theobject-carrier J and the pillar G, a parallelogram. These levers holdand guide the obj cot-carrier J, referred to hereinafter, which hangs onpoints 6 e, between the bifurcated arms of the levers H H The upperlever H extends in either direction from its fulcrum-points e, and thedistance from these points e to the supporting-points e of the objcot-carrier is the same as that from c to the pivot-points e -near theopposite end of the leverfrom that carrying the obj ect-carrier-by whichthe lever is connected with a screw-nut K, mounted upon a screw-threadedspindle K, which is an element of the micrometer mechanism to behereinafter described. By turning the spindle K in one direction or theother the nut K is moved up or down, and, through the lever H, theobject-carrier is to the same extent, but in the opposite direction,lowered or raised, the amount of lowering of the nut determining thethickness of the sheet or blade to be cut when the knife is moved acrossthe face of the object. While the movements of the spindle K, justdescribed, cause the rear end of the lever H to move in the arc of acircle, there is no binding of the nut K upon the spindle, because notonly is the nut pivotally connected with the lever, but the lower end ofthe spindleshaft is supported by a ball-and-socket or cup bearing, asrepresented in Figs. 3, 10, and 11, which permits of a slight tipping ofthe shaft. Moreover, in practice the nut N is so adjusted on the spindlethat the latter does not occupy a true vertical position when the leverII is absolutely horizontal, but assumes the vertical position when thelever has made about one-eighth of its travel. In consequence of thisdeviation of the spindle K from the true vertical position under certainconditions the movements of the nut K and of the object-holder willgenerally be slightly smaller than what is shown on themicrometer-scale, to be hereinafter described; but as the difierence isso exceedingly smallonly a fraction of one ten-thousandth of an inch-itmay in practice be disregarded altogether.

The object-carrier must be so arranged as to allow it to be moved indifferent directions in the most exact and at the same time in as easyand quick a manner as possible.

The plate or platform J carrying the obj ect J, is to be turned roundits axis and must be secured in any desired position. To permit of thisadjustment, the object-carrier is of peculiar construction, as will bedescribed. It is made hollow, as represented in Fig. 7, and a spindle f,screw-threaded at its upper end, extends through such holder and servesas the means for connecting the platform J 2 upon the holder J Thisspindle is provided at its lower end with a milled head or disk g, bywhich it may be operated, and upon the upper screw-threaded end of thespindle there is fixed a nut or clamping-piece h, which is situated in arecess j in the holder J The object-platform J 2 is engaged by thescrewthreaded end of the spindle and is held thereby, as clearlyrepresented in Fig. 7. The nut It operates to prevent the spindle frombecoming entirely disengaged from the objectcarrier when the platform J2 is removed, and also by bearing against the shoulder j serves to clampthe platform securely to the upper face of the holder.

In order that the object may be given the required adjustments, as aboutthe center a 6, Fig. 7, Iprovide the holder.) witha sphericalshapedbase, which is fitted to and rests in a bed 2 arranged within theobject-carrier J. To adjust the object holder and platform and to firmlyhold them after adjustment, I provide the following-described mechanism:A tubular piece It, provided with a rectangular head Figs. 7 and 8, isfirmly secured to the holder J The spindle f passes through this piece70. Adj Listing-screws Z and Z pass through the Walls of theobject-carrier and bear against contiguous faces of the head 71a of thepiece It, while the pressure-pins m m operated upon by the springs 011.m bear against the said head directly opposite to the saidadjusting-screw. By these means the head 70, and with it theobject-plate, may be exactlyadjusted toanydesiredposition. The point 0c, Fig. 7, is the center of the spherical end of the holder J and it isaround this center that the adjustments, by means of theadjusting-screws Z and Z take place, and as this point is within thebody of the object upon the platform J it is evident that theadjustments of the holder J as described, will cause very slight lateralmovements of the object.

The obj ect-holder J 3 must be capable of being securely held in anyposition to which it may be adjusted. To this end a head a, providedwith a tubular extension n and a circular end or head a atthe end of theextension opposite to the head 01, is mounted upon the spindle f belowthe head It. Two bolts 07. pass through the head a, to which they maybesecured by the nuts a through slots 75 Fig. 8, in the head 70' and intoa nut of, to which they are secured, the nut n and head a being thusunited.

On turning the head at in one directionsay from the left toward theright side-.the nut 42 is moved upward and presses the friction-plate 0against the lower side of the bedt' with the effect of fixing theobject-holder J 3 in its bed, so as to prevent any movement of saidholder. Before operating the screws Z or Z for adjusting theobject-holder the head 42 of course is to be turned backward, in thiscase from the right to the left hand. The amount by which the head at isturned for fixing or releasing the object-holder is about one-eighth ofa whole rotation.

Another feature of myinvention comprises the device or mechanism foradjusting the thickness of the sheet to be cut from the object to beexamined. The shaft L of the micrometric screw K is provided with acrank handle 19 for roughly adjusting the object; but for fineadjustment a device is employed, referred to hereinafter, and arrangednear the lower end of the micrometric screw. A ratchet-wheel having, forinstance, five-hundred teeth is keyed on the shaft close to its lowerextremity. N is a segment of a ring arranged concentrically to the axisof shaft L and fixed on the plate B, the graduation on the surface ofsaid segment corresponding to the pitch of the Wheel M. Two arms (1 and0, Figs. 9, 10, and 11, are arranged to turn about the axis .2 z of theshaft L, the former, (1, being marked with the index-line q and providedwith a set-screw q to retain the arm (1 in any desired place on thesegment N, the latter, 0', forming the bearing of a piece 1" by means ofpoints 0", carried by the bifurcated end of the arm '1'. Stay-bolts sand s, the one fixed in the foundation-plate B and the other in the armq, limit the swinging motion of the arm '1', that may be imparted to itby a handle 0, fixed to the piece 0". Thus the actual position of thearm q determines the angle of the movement of arm r. Piece 1"furthermore forms the carrier of a ratchet-tooth r engaging with theratchet-wheel M.

Now in order to adjust the thickness of the blade or sheet to be out theoperator, after having fixed the arm q in the required position, moves,by means of the handle W, the arm r toward the left side until themovement is arrested by the stud s and then toward the right side by somuch until the movement is stopped by the stud s. The drawings, Figs. 2and 9, clearly illustrate that the ratchettooth r engages with the wheelM only during the last-mentioned motion of the arm r,with the effect ofturning said wheel, and with it the micrometric screw K, of movingdownward the nut K and raising the object I. On moving the handle 1backward-that is, from the right to the left handth-e piece r turnsabout its axis, throws the tooth 0 out of gear with the wheel M, (theextent of the movement of the piece 0 being limited by the engagement ofthe pin 25 with the bifurcated end of the arm 1 and thus the partsreturn to the left side without moving the wheel M.

What I claim as my invention, and desire to secure by Letters Patent, is

1. In a microtome, the combination of the knife F having a sphericalpivot c on one end and a cylindrical pivot c on the other,with aknife-carrierE, the block D of which is guided in an acute angle bymeans of slide-pieces a, substantially as and for the purpose specified.

2. In a microtome, the combination of the object-carrier J with thelevers H, H supportedin the pillar G, and with the nut K of amicrometrio screw K, said nut hanging between point-s e e at the end oflever II, essentially as set forth.

3. In a microtome, a micrometric screw, a shaft L, and a crank-handle19, located at the upper end of said shaft for roughly adjusting theobject, in combination with a handle T and a ratchet -tooth r revolubleupon the lower end of shaft L, and the ratchet-Wheel M, fixed to saidshaft engaging with the ratchet-tooth for effecting fine adjustments,substantially as and for the purposes hereinbefore set forth. 1

4:. In a microtome,the combination with the obj cot-carrier J, of aplate or platform J 2 the upper face of which is arranged below thecenter 0 e of the spherical bed of said carrier and the spherical bed inwhich the carrier is mounted, substantially as and for the purposeshereinbefore set forth.

5. The combination of the platform or object-plate J an object-holder towhich said platform is adapted to be secured provided with an axialrecess j, a screw-threaded spindle adapted to engage with the platformand passing through the said object-holder and provided with anoperating-head, and a nut or clamping-piece h fixed to the spindle andsituated in the said recess in the objectholder, substantially assetforth.

6. In a microtome, the combination of the object-holder J 3 providedwith a tubular extension k threaded on its outer surface, anut nengaging therewith, a friction-plate o, the bed 2', a milled disk '11,and means for connecting said nut with said milled disk, substantiallyas and for the purposes hereinbe fore set forth.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

- WILHELM LOW. Witnesses:

ERNST KAUFMANN, JACOB ADRIAN.

